The purpose of this report is to provide an understanding on the actor ecosystems and critical actors in the reuse of concrete elements. To enable the reuse of precast concrete elements, many different actors must collaborate. They include key value chain actors within the construction industry, their subcontractors, and supporting actors, such as authorities. As the reuse of concrete elements provides new challenges and opportunities for the construction industry, it is important to understand the actor ecosystem: the variety of actors, their roles and tasks. Compared to conventional construction projects, the reuse of precast concrete elements requires new skills and new ways of thinking. Therefore, the actors involved have to expand their conventional roles or even take on new roles within the concrete element reuse ecosystem. The current report provides new understanding on the roles and tasks needed to enable concrete element reuse, and how these tasks can be distributed between the value chain partners. The findings are based on data collected through interviews, ethnographic follow-up and from secondary sources. Related results of the ecosystem mapping have also been published in a journal article and a conference article.